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Finding the Fourth Proportional to 839.08, 1,157.52 and 728.40

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Solution

The fourth proportional to 839.08, 1,157.52 and 728.40 is: 1,004.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.08 : 1,157.52 = 728.40 : x
  2. Step 2: Convert to fraction form
    839.08/1,157.52 = 728.40/x
  3. Step 3: Cross multiply
    839.08x = 1,157.52 × 728.40
  4. Step 4: Simplify right side
    839.08x = 843,137.57
  5. Step 5: Solve for x
    x = 843,137.57/839.08
  6. Step 6: Final answer
    x = 1,004.84

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.